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Pregnancy Delivery Date Formula:
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The Pregnancy Delivery Date Calculator estimates the expected due date (EDD) based on the first day of the last menstrual period (LMP). This calculation follows Naegele's rule, adding 280 days (40 weeks) to the LMP date.
The calculator uses the standard obstetric formula:
Where:
Explanation: This calculation assumes a regular 28-day menstrual cycle and ovulation occurring on day 14. The 280 days represents the typical human gestation period from the first day of the last menstrual period.
Details: Accurate due date estimation is crucial for prenatal care planning, monitoring fetal development, scheduling important tests, and preparing for delivery. It helps healthcare providers track pregnancy progress and identify potential complications.
Tips: Enter the first day of your last menstrual period in the date field. Ensure the date is accurate for the most reliable estimation. The calculator will provide the estimated due date based on standard obstetric calculations.
Q1: How Accurate Is The LMP Method?
A: The LMP method provides a good estimate but may vary based on menstrual cycle regularity. Ultrasound dating in early pregnancy is often more accurate.
Q2: What If My Cycle Is Not 28 Days?
A: For cycles longer or shorter than 28 days, adjustments may be needed. Consult with your healthcare provider for personalized calculation.
Q3: When Should I Confirm With Ultrasound?
A: Early pregnancy ultrasound (6-12 weeks) provides the most accurate dating and is recommended to confirm the due date.
Q4: What Percentage Deliver On Their Due Date?
A: Only about 5% of women deliver exactly on their due date. Most deliver within two weeks before or after the estimated date.
Q5: Can This Calculator Be Used For IVF Pregnancies?
A: For IVF pregnancies, the calculation is based on the embryo transfer date rather than LMP for greater accuracy.